G30 HDR 0.1 SPI and Graphical Display

i’m back for ask one help a the community. Few week ago i wrote i had a problem (of velocity communication) to control one graphic display 240*320 with I2CBus . Someone told me i need the use the SPI and i did, with 3 74c595 . Now the problem look the same when i want refresh the display is so slow like more then 3 minuts like with I2CBus. I don’t have an oscilloscope for see the signal but i try to change the clock in the SPI configuration and i saw that i can write 1000 or 10000 or 500 and the refresh take the same time.Someone have sone idea ?

Thank you so much

Can you post your code? Also, the specifications of your display and your setup? If the SPI bus speed change has no effect of the refresh speed of your display, likely you have something else going on in your code which is slowing you down.